System and method for measuring pressure applied by a piezo-electric pump

Abstract

A system and method for measuring the pressure provided by a disc pump is disclosed. The disc pump comprises an actuator mounted within the disc pump on a flexible skirt that allows the actuator to oscillate for generating air flow through the cavity of the pump and allows the actuator to be displaced with increasing pressure to a load. The actuator moves from a rest position when air begins flowing through the cavity to a biased position when the load is fully pressurized or depressurized depending on the direction of fluid flow through the cavity. The pump further comprises a sensor which measures the displacement of the actuator at any position between the rest position and the biased position as fluid begins flowing through the cavity to pressurize or depressurize the load. The pressure being delivered by the disc pump is determined as a function of the displacement of the actuator.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS[0001]This application claims the benefit of U.S. Provisional Application No. 61 / 371,954, filed Aug. 9, 2010, and is hereby incorporated by reference.BACKGROUND[0002]1. Field of the Invention[0003]The illustrative embodiments of the invention relate generally to a pump for fluid and, more specifically, to a pump in which the pumping cavity is substantially elliptical in shape having end walls and a side wall with an actuator disposed between the end walls. The illustrative embodiments of the invention relate more specifically to a disc pump having a valve mounted in the actuator and / or one additional valve mounted in one of the end walls.[0004]2. Description of Related Art[0005]The generation of high amplitude pressure oscillations in closed cavities has received significant attention in the fields of thermo-acoustics and pump type compressors. Recent developments in non-linear acoustics have allowed the generation of pressure waves with higher...

AI Technical Summary

Benefits of technology

[0011]In addressing measurement and control issues of tissue treatment systems, which may include a disc pump or micro-pump, the principles of the present invention may be utilized to measure the pressure being generated by the disc pump to more effectively and economically control the operation of the disc pump. The disc pump includes an actuator that vibrates within a cavity to generate a radial pressure wave to provide a reduced pressure for application to a load or tissue site as described above. Displacement of the actuator may be measured using one or more sensors. Pressure being generated by the disc pump for the tissue site may be determined in response to the measured displacement of the actuator. A drive signal for the actuator may be adjusted to control operation and, consequently, displacement of the actuator to reach a desired pressure at the tissue site.

Problems solved by technology

However, high amplitude acoustic resonance has not been employed within disc-shaped cavities in which radial pressure oscillations are excited until recently.

Images